1. Field of the Invention
The present invention relates to a film substrate on which a semiconductor device chip is to be mounted, to a semiconductor device, to a method of manufacturing the film substrate, to a method of manufacturing the semiconductor device, and to a method of manufacturing a circuit board with the semiconductor device.
2. Description of the Related Art
A conventional method of mounting a semiconductor device chip on an insulative film on which a conductive pattern has been formed will be described below with reference to FIG. 18A and FIG. 18B to FIG. 22A and FIG. 22B.
FIG. 18A is a perspective view sowing an external appearance of a semiconductor device chip 1 (semiconductor integrated circuit device chip, etc.), and FIG. 18B is a cross-sectional view taken along a line B—B of FIG. 18A. The surface of the semiconductor device chip 1 is formed with a plurality of stud bumps 2 as an external terminal.
FIG. 19A is a plan view showing a tape-like insulative film 3 on which a conductive pattern (wiring pattern) 4 has been formed, and FIG. 19B is a cross-sectional view taken along a line B—B of FIG. 19A. The structure shown in FIG. 19A and FIG. 19B is obtained in the following manner. That is, a conductive metal foil (e.g., copper or aluminum foil having a thickness of about 35 μm) is stuck on the insulative film 3 (having a thickness of about 25 to 75 μm) via a bonding (adhesive) agent 5. Thereafter, the conductive metal foil is patterned by lithography and etching.
As illustrated in FIG. 20A and FIG. 20B, an anisotropic conductive resin 6 is stuck to a chip mounting region on the surface of the insulative film 3 with the conductive pattern 4 thus obtained. Further, as shown in FIG. 21A and FIG. 21B, the semiconductor device chip 1 is mounted on the anisotropic conductive resin 6 by flip chip method. In the above manner, a tape-like film substrate is obtained.
Thereafter, as illustrated in FIG. 22A, a film having a predetermined shape is separated from the tape-like film substrate by a press machine. By doing so, a film substrate piece shown in FIG. 22B is obtained.
The film substrate piece thus obtained is mounted on circuit boards such as PCB (Printed Circuit Board) and FPC (Flexile Printed Circuit board) in the following manner.
First, as illustrated in FIG. 23A and FIG. 23B, a conductive bonding agent 10 is stuck onto a circuit board 8 on which passive elements 7 and connecting terminals 9 are formed. In this case, anisotropic conductive resin may be used as the conductive bonding agent 10.
As shown in FIG. 24, the film substrate piece obtained in the step of FIG. 22A and FIG. 22B is placed on the circuit board 8 using an adsorption apparatus 11. Then, connection is made between the conductive pattern 4 formed on the film substrate piece and the connecting terminal 9 formed on the circuit board 8 by the conductive bonding agent. When making the above connection, thermocompression bonding (200° C., about 20 seconds) is carried out by a thermocompression bonding apparatus 12.
However, the above conventional method has the following problems because the film substrate piece is separated from the tape-like film substrate, and thereafter, the separated film substrate piece is mounted on the circuit board.
More specifically, the film substrate piece must be individually handled; for this reason, handling of the film substrate piece is difficult. As a result, it is difficult to achieve the improvement of productivity by automation. Further, if the size of the film substrate piece is made small, it is impossible to use the adsorption apparatus 11 and the thermocompression bonding apparatus 12 together. As a result, as seen from FIG. 25A and FIG. 25B, two steps must be carried out; for this reason, this is a factor of increasing the number of steps. Further, as shown in FIG. 26, the conductive bonding agent 10 projects from the peripheral edge portion of the film substrate piece. As a result, for example, there is a possibility that the bonding agent adheres to the thermocompression bonding apparatus 12. In order to prevent the above problem, the film substrate piece must be made large; for this reason, this does not meet the needs of miniaturization.
As described above, according to the conventional technique, the film substrate piece is separated from the tape-like film substrate, and thereafter, the separated film substrate piece is mounted on the circuit board. For this reason, there are various problems that handling is troublesome, miniaturization is difficult, and productivity is worse.
On the other hand, the following technique has been disclosed in JPN. PAT. APPLN. KOKAI Publications No. 3-84955 and No. 6-53288. According to the technique, slit is previously formed in the tape-like film substrate on which semiconductor device chips are mounted. The inner region of the slit is provided with a semiconductor device chip and a conductive pattern connected thereto. The slit is previously formed, and thereby, the film substrate piece is easy to separate from the tape-like film substrate.
However, according to the method disclosed in the above conventional technique, the inner and outer regions of the slit are merely connected by a portion between adjacent slits. In other words, before separation, the inner region of the slit is held only by the portion between adjacent slits. Therefore, the holding strength of the inner region of the slit is low; for this reason, there is a problem that handling of the tape-like film substrate is difficult.